1. Field of the Invention
The present invention relates to an automatic cover-opening device, and more particularly to an automatic cover-opening device that can be applied for insertion of an object.
2. Description of Related Art
A vessel, such as a pencil sharpener, usually has a cover to close an opening of the vessel and to prevent particles or scraps in the vessel from discharging from the opening of the vessel. China Patent No. 202573548, entitled “environmentally friendly pencil sharpener” (hereinafter referred to as '548 patent), substantially comprises two sliding panels pivotal relative to each other. Each sliding panel has a conical recess corresponding in position to a pencil hole of the sharpener. Accordingly, when a pencil is inserted into the sharpener, the pencil can push the sliding panels to pivotally rotate along the conical recesses to open the pencil hole. Consequently, the pencil can be sharpened by the blade in the sharpener.
However, the conventional cover-opening device of the '548 patent can only be applied to a sharpened pencil having a conical tip. When a brand new, unsharpened pencil having a flat end is inserted into the sharpener, the conical recesses in the sliding panels cannot transfer the axial insertion force of the flat end of the pencil to lateral force, which is for pushing the sliding panels to move. Therefore, the sliding panels are not pivoted relative to each other, and the pencil hole in the sharpener cannot be opened. Moreover, the sliding panels will be closed to each other due to the normal force of the pencil. Therefore, the conventional cover-opening device is limited and inconvenient in use.
To overcome the shortcomings, the present invention tends to provide an automatic cover-opening device to mitigate or obviate the aforementioned problems.